Electroantennogram responses of an invasive species fall webworm (Hyphantria cunea) to host volatile compounds

Electroantennogram responses of fall webworms(Hyphantria cunea) to 55 host volatile compounds were conducted.Results showed that male moths were more responsive to trans-2-hexenyl acetate,nonanal,hexanal,trans-2-hexenal,hexanol,isoamyl acetate,acetic acid cis-3-hexenyl ester,ethyl acetoacetate,citronellal and(+)-citronellal,and females were more responsive to hexanol,hexanal,acetophenone,isoamyl acetate,nonanal,trans-2-hexenal,acetic acid cis-3-hexenyl ester,citronellal,cis-3-hexen1-ol and trans-2-hexen-1-ol.Seven bioactive compounds were also selected for further dosage response experiments,and a positive correlation was found between the fall webworm and the tested compounds.A maximum dosage level of 1000 g was tested and found to elicit significantly higher activity from male moths compared with lower(1,10,100 g) concentrations.     

Synthesis of novel active ester ether resin and its effects on positive thermal CTP plates

A novel active ester ether resin, consisting of p-hydroxyphenylacetic acid and a mixed-phenol novolac resin, was produced by the addition of ethyl vinyl ether to a carbonyl novolac resin. This study investigated the conditions of its synthesis and characterized its structure using infrared and 1 H NMR spectroscopies, and gel-permeation chromatography. Its solubility in alkaline solution differed greatly before and after decomposition. The results of thermal gravimetric analysis confirmed the formation of an active ester ether resin of p-hydroxyphenylacetic acid and novolac resin. The resin had acidolysis activity at room temperature and pyrolysis activity at high temperatures (140-200°C) and could be used in the imaging layer of a positive thermal plate for computer-to-plate processes as an inhibitor/accelerator to improve its alcohol resistance, alkali resistance, sensitivity, lattice point reducibility, and developing tolerance.     

Preparation and Characterization of Ester from Rosin Acrylic Acid Adduct and Hydroxyethyl Methacrylate

1 Results Rosin is a sort of important renewable resources,which is a foremost product of our country forestry. It has very important meaning to modify the rosin based on its molecule structure and active group, to develop some deep processing products, and to endure with rosin new characteristic[1]. This work uses the rosin and acrylic acid to form rosin adduct, and then reacted with 2-hydroxyethyl methacrylate (HEMA) to form ester under the different condition. The effect of different ratios with the adduct and HEMA, catalyst types and levels on the esterification was investigated. The molecular structure of the adduct and the ester was characterized with IR spectrum. Their thermal stabilities were conducted with thermal analyzer. Experiment results show that the rosin ester was prepared successful, the best esterification condition was found out. The thermal stability of the rosin ester from acrylic acid rosin and HEMA was improved. The rosin ester may be used as negative photoresist[2].     

Concise Synthesis and Fertility-Promoting Activity of Thiamidol

In order to make the synthetic route of Thiamidol more efficient and easier to scale up, a new method was developed. The compound 2,4-dihydroxyacetophenone was dissolved in ethyl acetate and brominated with cupric bromide. After bromination, the mixture was filtered to remove cuprous bromide. The obtained ethyl acetate solution containing 2-bromo-1-(2,4-dihydroxyphenyl)ethanone was directly reacted with(2-methylpropanoyl)thiourea to obtain the precipitate of Thiamidol hydrobromide. The precipita...     

玉米蛋白粉脂溶性成分研究

从玉米蛋白粉中分离得到四种结晶.经鉴定为:β—Sitosteral)(Ⅰ);玉米黄质(Zeaxanthin)(Ⅱ);棕榈酸一2—羟基—1—羟甲基乙基酯(Hexadecanoic acid—2—hydroxy—1—(hydroxymethyl)ethyl ester)(Ⅲ);棕榈酸—β—sitosteryl palmitate)(Ⅳ).     

Mechanism of Citric Acid Crosslinking in Cotton Fabrics

Citric acid (CA), which is cheap and nontoxicity, was regarded as the most likely formaldehyde - free durable press finishing reagent to be commercialized. To improve the drawbacks of CA finishs such as yellowing and less durability to home laundering, further research should be done. In this paper, a method had been found to differentiate ester crosslinkings from ester attachments on CA treated fabric and the variations of both ester crosslinkings and ester attachments under different curing conditions were also studied.     

败酱草化学成分研究

研究白花败酱草的化学成分,以95%乙醇溶液提取白花败酱草,依次采用石油醚、二氯甲烷、正丁醇对提取物进行萃取.正丁醇提取物分别采用硅胶柱色谱、ODS柱色谱以及葡聚糖凝胶色谱等技术进行分离,然后应用半制备型高效液相色谱进行纯化,共得到7个化合物.通过核磁共振技术,结合相关文献对比后确定全部化合物结构.分别为Caffeic acid ethyl ester (1),Caffeic acid n-butyl ester(2),Apigenin (3),Luteolin (4),Menthalignin (5),Methyl 2-(4-hydroxyphenyl) acetate (6),trans-Ferulic acid (7).其中化合物1～3,6,7均为首次从该植物中分离得到.     

Study on the Synthesis of Monoolein and Its Practical Application in Wool Spinning

Oleic acid was used as a raw material to synthesize mo-noolein by means of esterifying and ester exchanging. Through synthetically judging every possible influential factor, a new method was found to synthesize moloolein under moderate condition. Then, monoolein was applied as a main component to mix with Polyoxyethylene alkyl-phenol ether Sodium Phosphate and Polyoxyethylene al-kylphcnol ether - 10 for preparing a new kind of wool lubricant. The testing its performances in wool spinning were conducted.     

Analysis of fragrance composition in three cultivars of <Emphasis Type="Italic">Osmanthus fragrans</Emphasis> Albus group flower by gas chromatography-mass spectrometry

With supercritical CO2 fluid extraction(SCFE), essential oil was extracted from three cultivars of Xianning osmanthus. The fresh osmanthus flower was processed with a petroleum ether digestion method to produce the extractum. The yields of essential oil and extractum were 0.19 % and 0.13 % (m/m) respectively. The essential oil and fragrance composition and content extracted were analyzed with gas chromatography-mass spectrometer (GC-MS). The result showed that essential oil contained 36.99%(area/total area) of ionone, ionol and 13.11% of linalool; ionone and ionol contained in extractum were as high as up to 33.33%, while linalool up to 21.92%. Whether essential oil or extractum contains only about 40% fat acid and other ester matters. None of environmental estrogen (phthalic ester) was found in fragrance ingredients. The result also showed that the quality of O. fragrans Albus group fragrance in Xianning is better than that produced in Hangzhou and Anhui districts.     

Thermosensitive self-assembly behaviors of novel amphiphilic polyphosphazenes

A series of amphiphilic thermosensitive polyphosphazenes （PNIPAm-g-PPP） bearing N-isopropylacrylamide oligomers （oligo-PNIPAm） and glycine ethyl groups （GlyEt） as co-substituents have been synthesized via polymer substitute reaction. UV-visible spectra indicated that the aqueous solution of PNIPAm-g-PPP exhibited the lower critical solution temperature （LCST）. Furthermore, the LCST was seriously influenced by the substitution ratios of PNIPAm to GlyEt in the copolymer. The more GlyEt the copolymer contained, the lower LCST it had. The critical association concentration （cac） of copolymers was determined by fluorescence probe method. It was found that cac was decreased with increasing GlyEt content of polyphosphazene. Also the formation of self-assembled micelles or nano-particles was confirmed by TEM.     

Crocin Synthesis Mechanism in Crocus sativus

Saffron （Crocus sativus） cells can synthesize crocin, crocetin digentiobiosyl ester, in suspension cultures. The crocin family biosynthesis mechanism was studied using high pressure liquid chromatography （HPLC） to determinate the glucosyltransferase activity and to develop a method for synthesizing medicine from saffron cells. Previous studies indicated that two glucosyltransferases might be involved in the formation of crocetin glucosyl- and gentiobiosyl-esters. GTasel formed an ester bond between crocetin carboxyl groups and glucose moieties while GTase2 catalyzed the formation of glucosidic bonds with glucosyl ester groups at both ends of the molecule. These enzymes can catalyze the formation of crocetin glucosides in vitro. GTasel activity is higher during the first four days of crocin glucosides biosynthesis, but decreases after four days. The formation and accumulation of crocin increase during the first six days and stabilized on the eighth day.     

The uptake of ethyl iodide on black carbon surface

The importance of the iodine chemistry in the atmosphere has been demonstrated by recent obserations. The uptake of ethyl iodine on black carbon surface was inestigated at 298 K for the first time. Degussa FW2 （an amorphous black carbon comprising medium oxides） was used as black carbon sample. Black carbon surface was found to be deactiated in reaction with C2H51, and the uptake coefficient （r） was dependent on the time of exposure. The alue of （2.3±0.9）×10^-2 was determined for the initial uptake coefficient （No）. The result suggests that the heterogeneous loss of C2H51 on carbonaceous aerosols may be important under the atmospheric conditions.     

Biogenic amino acid methionine-based corrosion inhibitors of mild steel in acidic media

N,N-Diallyl methionine ethyl ester hydrochloride 5 underwent alternating copolymerization with SO_2 via the Butler cyclopolymerization protocol in dimethyl sulfoxide(DMSO) to give water-soluble cycloterpolymer 6 with a ～1:1 molar ratio of sulfide and sulfoxide groups as a result of oxygen transfer from DMSO. Half of the sulfide groups in 6, upon oxidation with H_2O_2, afforded polymer sulfoxide 7 and polymer sulfone 8. The solution properties of these polymers were determined via a viscometric technique. The thermal stability of these polymers was determined by thermogravimetric analysis. The inhibition efficiency obtained from gravimetric mass loss, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques agreed well with each other. The corrosion efficiencies increase with increasing concentration of the polymers. At a polymer concentration of 175 mM, the maximum inhibition efficiency of copolymer compounds 6–8 was determined to be 92%, 97%, and 95%, respectively. The synthesized polymer compounds acted as mixed-type inhibitors. Polymer compound 7 adsorbed onto the metal surface via chemisorption and physisorption and obeyed Langmuir, Temkin, and Freundlich adsorption isotherms. Analyses by X-ray photoelectron spectroscopy and scanning electron microscopy–energy-dispersive X-ray spectroscopy indicated that the adsorbed polymers formed a thin film on the metal surface and prevented further corrosive attack.     

Rapid Screening of chloramphenicol in Turbot with photobacterium phosphoreum DB

A new,simple,rapid microbial assay was put forward for the detection of chloramphenicol(CAP)residues in Turbot muscles using luminescent bacteria DB(Photobacterium phosphoreum)as test organ-ism.By the luminescence inhibition of DB,the concentrations of CAP were determined.CAP spiked inTurbot muscle tissues ranging from 0.5 to 100μg/kg was extracted using ethyl acetate and hexane.Themethod had a good recovery of 93.69% with a minimum detection limit of 0.65μg/kg.It can be per-formed within 30min followin...     

《Journal of Wuhan University(Natural Science Edition)》Vol.50 No.6, 2004 Abstract

● P698 702　 Synthesis of Novel Biodegradable AliphaticPolycarbonate with Ester GroupsCHENG Si xue, WANG Hao, WANG Lian sheng, ZHUO Ren xi(Key Laboratory of Biomedical Polymer Materials, Ministry of Education, Wuhan University,Wuhan 430072, Hubei, China)　　Abstract: Six membered cyclic carbonate 5,5 dimethoxycarbonyl 1,3 dioxan 2 one was synthesized by thereaction between dimethyl 2, 2 dihydroxymethylmalonate and ethyl chloroformate. A novel aliphatic polycar bonate was obta…     

Photopromoted carbonylation of olefins with carbon dioxide and labelling studies with ^13CO2 and ^13CH3OH

Photopromoted carbonylation of olefins with carbon dioxide can be completed in ambient conditions (room temperatures and atmospheric pressure) by Co(OAc)2 catalysis. It was found that in carbonyl carbons of methyl ester of aliphatic acid 50% is from CO2 and the other 50% from CHsOH by labelling experimental with ^13CO2 and ^CH3OH.     

Near-net shape processing of spherical high Nb-TiAl alloy powder by gelcasting

Spherical Ti-45Al-8.5Nb-(W,B,Y) alloy powder prepared by an argon plasma process was near-net shape by gelcasting. In the non-aqueous system, methaerylate-2-hydroxy ethyl, toluene, benzoyl peroxide, and N,N-dimethylaniline were used as the monomer, solvent, initiator, and catalyst, respectively. To improve sintering and forming behaviors, many additives were included in the suspension. The concentrated suspension with a solid loading of 70vol% was prepared. The high Nb-TiAl powder was analyzed by electron microscopy and X-ray diffraction. It was found that the green bodies had a smooth surface and homogeneous microstructure, exhibiting a bending strength as high as 50 MPa. After sintering at 1480℃ for 2 h in vacuum, uniform complex-shaped high Nb-TiAl parts were successfully produced.     

Synthesis and insecticidal activities of new pyrethroid acid oxime ester derivatives

A series of compounds containing oxime-ester linkage in place of the ester linkage in pyrethroid ester are designed and prepared. Bioassay data of insecticidal activities of these compounds on Ostrinia nubilalis (H.) and Culex pipines (L.) are presented. Among them 4-dimethyaminobenzaldehyde oxime ester of 2,2,3,3-tetramethylcyclopropanecarboxylic acid and 4-dimethyamino benzaldehyde oxime ester of cyclopropanecarboxylic acid are found to be potent insecticide against Ostrinia nubilalis (H.). Structure-activity relationship of the compounds is discussed.     

A potential approach to replace sulfurized olefins with borate ester containing xanthate group in lubricating oil

To develop a potential substitute for sulfurized olefins, a borate ester derivative containing xanthate group （titled BXT） was synthesized and characterized. Meanwhile, its tribological properties in rape-seed oil were evaluated using four-ball tribometer. The results indicate that BXT shows excellent tri- bological capacity such as load-carrying, friction-reducing and antiwear property. Moreover, the synthesized compound has no noticeable odor, shows little corrosion to copper, and exhibits better thermal stability compared with sulfurized olefins. In order to study the action mechanism of BXT in friction process, analysis of the worn surface was carried out using a three-dimensional non-contact surface profilometer and XPS analyzer.     

Flotation separation of arsenopyrite from several sulphide minerals with organic depressants

In this paper, the separation of arsenopyrite from chalcopyrite, pyrite, galena with organic depressants （guergum and sodium humic ） was discussed, and the functioning mechanism of those organic depressants was discussed. The experimental results of monomineral flotation indicated that both guergum and sodium humic have depressing effect on arsenopyrite in the presence of ethyl xanthate. Guergum and sodium humic showed different depressing ability to pyrite, chalcopyrite and galena, and the higher the pH value in pulp, the stronger the depressing ability. Ultraviolet-Visible Spectrophotometric study showed that the adsorption layer of xanthate on surface of minerals had been desorhed by the two organic depressants, and the selective desorption of the collector layer was found from different minerals. The xanthate cover on minerals surface was set free when dosage of the organic depressants was high enough. For artificially-mixed minerals, the separation of arsenopyrite from other sulphides was successfully realized by controlling dosage of the organic depressants. And sodium humic had been concentrates in a commercial Lead-Zinc concentrator.